So that Delo 400 that sat on a shelf for 11 years I said i wouldnt use again well decided to pop it in the Caballero and its even worse then in the transam. To be fair both where new to me cars and the first UOA's i have done to them. I now have Mobil 0w-40 in them and should be getting another report back on the caballero within the next few days with 1500mi on it and from there i will really know. Maybe an excuse to do an LS swap on the caballero. One thing i am noticing it looks very similar to the trans am's UOA except a lot of moly seems to have disappeared. 250 in the transam to 40 here. Maybe i didnt shake it vigorously enough?
1987 GMC Caballero, 11 year old Chevron Delo 400 LE 5w-40, 2000mi oci
- Thread starter BlueRaven
- Start date
I think this may be coming from the GMC more so than the oil. The oil was sealed up for 11 years right? Won't know too much about the car until more test's are done. Did they put 305 engine in these? Viscosity, oxidation, & additives all appear relatively normal.
dnewton3
Staff member
When you get abnormally high numbers, the first thing to do is contact the lab and ask if they can rerun the tests. Often labs will hold onto the sample for a while before disposing of it, for this very reason.
At this point, I'm going to assume the test results were accurate ... If not, that would change all resultant suspicions.
- The Si is really high for only 2k miles. Air intake leak? Any recent work done to the engine that would indicate fresh silicone was used as a sealer?
- You have very high Fe also, but they didn't flag it. This along with the Si really points to an intake tract leak
- The Pb and Cu together indicate a bearing problem
- The fuel dilution alone isn't high enough to cause significant issues such as those above, but I'm curious if the engine ever gets a full warm up? Was the sample taken after a short drive?
- how many total miles on the Caballero? (wasn't on the report)
You mentioned the "transam" (Trans Am?) using this same oil ... any data on that UOA posted here? Link to that one?
At this point, I'm going to assume the test results were accurate ... If not, that would change all resultant suspicions.
- The Si is really high for only 2k miles. Air intake leak? Any recent work done to the engine that would indicate fresh silicone was used as a sealer?
- You have very high Fe also, but they didn't flag it. This along with the Si really points to an intake tract leak
- The Pb and Cu together indicate a bearing problem
- The fuel dilution alone isn't high enough to cause significant issues such as those above, but I'm curious if the engine ever gets a full warm up? Was the sample taken after a short drive?
- how many total miles on the Caballero? (wasn't on the report)
You mentioned the "transam" (Trans Am?) using this same oil ... any data on that UOA posted here? Link to that one?
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Miles on vehicle?
Here is a previous UOA from the same batch of oil in another car.
11 year old Chevron delo 400, 1500mi oci, 2002 trans am
Looks like I am not going to be using up the rest of the delo on my shelf. Put in some fresh Mobil 0w-40.
bobistheoilguy.com
Odometer is broken I want to say north of 200k but thats just guessing. I got the vehicle i want to say February of last year so i dont really have knowledge of its history. Changed the oil twice before this UOA it did have a small amount of sludge.
Yup its a 305
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305’s have problems with weak cams and aren’t a great engine.
Some of the wear is abrasive dirt from the Si, some is corrosion from sitting, and some is just a worn high-miles engine.
At some point there ‘could’ have been leaded gas or a leaded octane booster used that would cause higher lead.
BTW, neat car, got any pics?
Some of the wear is abrasive dirt from the Si, some is corrosion from sitting, and some is just a worn high-miles engine.
At some point there ‘could’ have been leaded gas or a leaded octane booster used that would cause higher lead.
BTW, neat car, got any pics?
1987 were roller cam in the car engines. And the camshaft was a late 70s early 80s problem.
Basically an el camino
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So it’s washing out debris from there being ‘a bit of sludge in the engine’, as you said. Delo is a very good oil, it’s not the oil that is the problem it’s the engine.
Yes, 305’s got ‘better’ in later years, but they were never a ‘strong’ engine. It’s in a cool, rare car, though - lot less GMC versions were made than Chev ones!
Yes, 305’s got ‘better’ in later years, but they were never a ‘strong’ engine. It’s in a cool, rare car, though - lot less GMC versions were made than Chev ones!
They were never powerful, but if reliability is what matters they were way up there. I tried to kill a couple of mine when the car was going to the scrap yard. The one with 332k miles refused to die.
Yup thats probably the likely reason not sure why i didnt think of that. All the delo is used up now though.
